Rosetta Code

Sudoku: Difference between revisions

Page Discussion

Sudoku (view source)

Revision as of 13:26, 11 April 2022

115,158 bytes added ,  2 years ago
m
→‎{{header|Phix}}: syntax coloured, made p2js compatible
m (→‎{{header|Phix}}: syntax coloured, made p2js compatible)
Line 8,154:
=={{header|Phix}}==
Simple brute force solution. Generally quite good but will struggle on some puzzles (eg see "the beast" below)
<!--<lang Phix>sequence board = split("""phixonline)-->
<span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span>
.......39
<span style="color: #004080;">sequence</span> <span style="color: #000000;">board</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">split</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"""
.....1..5
..3.5.8...39
..8.9..1.6.5
.7.3.5.2.8..
1 ..4.8.9...6
.7.9.8.2..5.
1.2.4...6..
4 ..79.8..5..""",'\n')
.2....6..
 
4..7....."""</span><span style="color: #0000FF;">,</span><span style="color: #008000;">'\n'</span><span style="color: #0000FF;">)</span>
function valid_move(integer y, integer x, integer ch)
for i=1 to 9 do
<span style="color: #008080;">function</span> <span style="color: #000000;">valid_move</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">ch</span><span style="color: #0000FF;">)</span>
if ch=board[i][x] then return 0 end if
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
if ch=board[y][i] then return 0 end if
<span style="color: #008080;">if</span> <span style="color: #000000;">ch</span><span style="color: #0000FF;">=</span><span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">][</span><span style="color: #000000;">x</span><span style="color: #0000FF;">]</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #004600;">false</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end for
<span style="color: #008080;">if</span> <span style="color: #000000;">ch</span><span style="color: #0000FF;">=</span><span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">y</span><span style="color: #0000FF;">][</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #004600;">false</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
y -= mod(y-1,3)
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
x -= mod(x-1,3)
<span style="color: #000000;">y</span> <span style="color: #0000FF;">-=</span> <span style="color: #7060A8;">mod</span><span style="color: #0000FF;">(</span><span style="color: #000000;">y</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">3</span><span style="color: #0000FF;">)</span>
for ys=y to y+2 do
<span style="color: #000000;">x</span> <span style="color: #0000FF;">-=</span> <span style="color: #7060A8;">mod</span><span style="color: #0000FF;">(</span><span style="color: #000000;">x</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">3</span><span style="color: #0000FF;">)</span>
for xs=x to x+2 do
<span style="color: #008080;">for</span> <span style="color: #000000;">ys</span><span style="color: #0000FF;">=</span><span style="color: #000000;">y</span> <span style="color: #008080;">to</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">+</span><span style="color: #000000;">2</span> <span style="color: #008080;">do</span>
if ch=board[ys][xs] then return 0 end if
<span style="color: #008080;">for</span> <span style="color: #000000;">xs</span><span style="color: #0000FF;">=</span><span style="color: #000000;">x</span> <span style="color: #008080;">to</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">+</span><span style="color: #000000;">2</span> <span style="color: #008080;">do</span>
end for
<span style="color: #008080;">if</span> <span style="color: #000000;">ch</span><span style="color: #0000FF;">=</span><span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">ys</span><span style="color: #0000FF;">][</span><span style="color: #000000;">xs</span><span style="color: #0000FF;">]</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #004600;">false</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
return 1
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end function
<span style="color: #008080;">return</span> <span style="color: #004600;">true</span>
 
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
sequence solution = {}
 
<span style="color: #004080;">sequence</span> <span style="color: #000000;">solution</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
procedure brute_solve()
for y=1 to 9 do
<span style="color: #008080;">procedure</span> <span style="color: #000000;">brute_solve</span><span style="color: #0000FF;">()</span>
for x=1 to 9 do
<span style="color: #008080;">for</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
if board[y][x]<='0' then
<span style="color: #008080;">for</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
for ch='1' to '9' do
<span style="color: #008080;">if</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">y</span><span style="color: #0000FF;">][</span><span style="color: #000000;">x</span><span style="color: #0000FF;">]<=</span><span style="color: #008000;">'0'</span> <span style="color: #008080;">then</span>
if valid_move(y,x,ch) then
<span style="color: #008080;">for</span> <span style="color: #000000;">ch</span><span style="color: #0000FF;">=</span><span style="color: #008000;">'1'</span> <span style="color: #008080;">to</span> <span style="color: #008000;">'9'</span> <span style="color: #008080;">do</span>
board[y][x] = ch
<span style="color: #008080;">if</span> <span style="color: #000000;">valid_move</span><span style="color: #0000FF;">(</span><span style="color: #000000;">y</span><span style="color: #0000FF;">,</span><span style="color: #000000;">x</span><span style="color: #0000FF;">,</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
brute_solve()
<span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">y</span><span style="color: #0000FF;">][</span><span style="color: #000000;">x</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">ch</span>
board[y][x] = ' '
if length(solution)<span thenstyle="color: return#000000;">brute_solve</span><span endstyle="color: if#0000FF;">()</span>
<span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">y</span><span style="color: #0000FF;">][</span><span style="color: #000000;">x</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">' '</span>
end if
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
return
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end if
<span style="color: #008080;">return</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
solution = board -- (already solved case)
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end procedure
<span style="color: #000000;">solution</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">deep_copy</span><span style="color: #0000FF;">(</span><span style="color: #000000;">board</span><span style="color: #0000FF;">)</span> <span style="color: #000080;font-style:italic;">-- (already solved case)</span>
 
<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span>
atom t0 = time()
brute_solve()
<span style="color: #004080;">atom</span> <span style="color: #000000;">t0</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">time</span><span style="color: #0000FF;">()</span>
printf(1,"%s\n(solved in %3.2fs)\n",{join(solution,"\n"),time()-t0})</lang>
<span style="color: #000000;">brute_solve</span><span style="color: #0000FF;">()</span>
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"%s\n(solved in %3.2fs)\n"</span><span style="color: #0000FF;">,{</span><span style="color: #7060A8;">join</span><span style="color: #0000FF;">(</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"\n"</span><span style="color: #0000FF;">),</span><span style="color: #7060A8;">time</span><span style="color: #0000FF;">()-</span><span style="color: #000000;">t0</span><span style="color: #0000FF;">})</span>
<!--</lang>-->
{{out}}
<pre>
Line 8,221 ⟶ 8,224:
contains 339 puzzles, can be run as a command-line or gui program, check for multiple solutions, and produce
a more readable single-puzzle output (example below).
<!--<lang Phix>(phixonline)-->
<lang Phix>-- Working directly on 81-character strings ultimately proves easier: Originally I
<span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span>
-- just wanted to simplify the final display, but later I realised that a 9x9 grid
<span style="color: #000080;font-style:italic;">-- Working directly on 81-character strings ultimately proves easier: Originally I
-- encourages laborious indexing/looping everwhere whereas using a flat 81-element
-- just wanted to simplify the final display, but later I realised that a 9x9 grid
-- approach encourages precomputation of index sets, and once you commit to that,
-- encourages laborious indexing/looping everwhere whereas using a flat 81-element
-- the rest of the code starts to get a whole lot cleaner. Below we create 27+18
-- approach encourages precomputation of index sets, and once you commit to that,
-- sets and 5 tables of lookup indexes to locate them quickly.
-- the rest of the code starts to get a whole lot cleaner. Below we create 27+18
 
-- sets and 5 tables of lookup indexes to locate them quickly.</span>
sequence nines = {}, -- will be 27 in total
cols = repeat(0,9*9), -- remainder(i-1,9)+1
<span style="color: #004080;">sequence</span> <span style="color: #000000;">nines</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{},</span> <span style="color: #000080;font-style:italic;">-- will be 27 in total</span>
rows = repeat(0,9*9), -- floor((i-1)/9)+10
<span style="color: #000000;">cols</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span><span style="color: #0000FF;">),</span> <span style="color: #000080;font-style:italic;">-- remainder(i-1,9)+1</span>
squares = repeat(0,9*9),
<span style="color: #000000;">rows</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span><span style="color: #0000FF;">),</span> <span style="color: #000080;font-style:italic;">-- floor((i-1)/9)+10</span>
sixes = {}, -- will be 18 in total
<span style="color: #000000;">squares</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span><span style="color: #0000FF;">),</span>
dotcol = repeat(0,9*9), -- same col, diff square
<span style="color: #000000;">sixes</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{},</span> <span style="color: #000080;font-style:italic;">-- will be 18 in total</span>
dotrow = repeat(0,9*9) -- same row, diff square
<span style="color: #000000;">dotcol</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span><span style="color: #0000FF;">),</span> <span style="color: #000080;font-style:italic;">-- same col, diff square</span>
 
<span style="color: #000000;">dotrow</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span><span style="color: #0000FF;">)</span> <span style="color: #000080;font-style:italic;">-- same row, diff square</span>
procedure set_nines()
sequence nine, six
<span style="color: #008080;">procedure</span> <span style="color: #000000;">set_nines</span><span style="color: #0000FF;">()</span>
integer idx, ndx
<span style="color: #004080;">sequence</span> <span style="color: #000000;">nine</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">six</span>
for x=0 to 8 do -- columns
<span style="color: #004080;">integer</span> <span style="color: #000000;">idx</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">ndx</span>
nine = {}
<span style="color: #008080;">for</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">to</span> <span style="color: #000000;">8</span> <span style="color: #008080;">do</span> <span style="color: #000080;font-style:italic;">-- columns</span>
ndx = length(nines)+1
<span style="color: #000000;">nine</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
for y=1 to 81 by 9 do
<span style="color: #000000;">ndx</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nines</span><span style="color: #0000FF;">)+</span><span style="color: #000000;">1</span>
idx = y+x
<span style="color: #008080;">for</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">81</span> <span style="color: #008080;">by</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
nine = append(nine,idx)
<span style="color: #000000;">idx</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">+</span><span style="color: #000000;">x</span>
cols[idx] = ndx
<span style="color: #000000;">nine</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nine</span><span style="color: #0000FF;">,</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">)</span>
end for
<span style="color: #000000;">cols</span><span style="color: #0000FF;">[</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">ndx</span>
nines = append(nines,nine)
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #000000;">nines</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nines</span><span style="color: #0000FF;">,</span><span style="color: #000000;">nine</span><span style="color: #0000FF;">)</span>
for y=1 to 81 by 9 do -- rows
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
nine = {}
<span style="color: #008080;">for</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">81</span> <span style="color: #008080;">by</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span> <span style="color: #000080;font-style:italic;">-- rows</span>
ndx = length(nines)+1
<span style="color: #000000;">nine</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
for x=0 to 8 do
<span style="color: #000000;">ndx</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nines</span><span style="color: #0000FF;">)+</span><span style="color: #000000;">1</span>
idx = y+x
<span style="color: #008080;">for</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">to</span> <span style="color: #000000;">8</span> <span style="color: #008080;">do</span>
nine = append(nine,idx)
<span style="color: #000000;">idx</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">+</span><span style="color: #000000;">x</span>
rows[idx] = ndx
<span style="color: #000000;">nine</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nine</span><span style="color: #0000FF;">,</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">)</span>
end for
<span style="color: #000000;">rows</span><span style="color: #0000FF;">[</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">ndx</span>
nines = append(nines,nine)
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #000000;">nines</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nines</span><span style="color: #0000FF;">,</span><span style="color: #000000;">nine</span><span style="color: #0000FF;">)</span>
if length(nines)!=18 then ?9/0 end if
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
for y=0 to 8 by 3 do -- small squares [19..27]
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nines</span><span style="color: #0000FF;">)!=</span><span style="color: #000000;">18</span> <span style="color: #008080;">then</span> <span style="color: #0000FF;">?</span><span style="color: #000000;">9</span><span style="color: #0000FF;">/</span><span style="color: #000000;">0</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
for x=0 to 8 by 3 do
<span style="color: #008080;">for</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">to</span> <span style="color: #000000;">8</span> <span style="color: #008080;">by</span> <span style="color: #000000;">3</span> <span style="color: #008080;">do</span> <span style="color: #000080;font-style:italic;">-- small squares [19..27]</span>
nine = {}
<span style="color: #008080;">for</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">to</span> <span style="color: #000000;">8</span> <span style="color: #008080;">by</span> <span style="color: #000000;">3</span> <span style="color: #008080;">do</span>
ndx = length(nines)+1
<span style="color: #000000;">nine</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
for sy=y*9 to y*9+18 by 9 do
<span style="color: #000000;">ndx</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nines</span><span style="color: #0000FF;">)+</span><span style="color: #000000;">1</span>
for sx=x to x+2 do
<span style="color: #008080;">for</span> <span style="color: #000000;">sy</span><span style="color: #0000FF;">=</span><span style="color: #000000;">y</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span> <span style="color: #008080;">to</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span><span style="color: #0000FF;">+</span><span style="color: #000000;">18</span> <span style="color: #008080;">by</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
idx = sy+sx+1
<span style="color: #008080;">for</span> <span style="color: #000000;">sx</span><span style="color: #0000FF;">=</span><span style="color: #000000;">x</span> <span style="color: #008080;">to</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">+</span><span style="color: #000000;">2</span> <span style="color: #008080;">do</span>
nine = append(nine,idx)
<span style="color: #000000;">idx</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">sy</span><span style="color: #0000FF;">+</span><span style="color: #000000;">sx</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span>
squares[idx] = ndx
<span style="color: #000000;">nine</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nine</span><span style="color: #0000FF;">,</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">)</span>
end for
<span style="color: #000000;">squares</span><span style="color: #0000FF;">[</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">ndx</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
nines = append(nines,nine)
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #000000;">nines</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nines</span><span style="color: #0000FF;">,</span><span style="color: #000000;">nine</span><span style="color: #0000FF;">)</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
if length(nines)!=27 then ?9/0 end if
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
for i=1 to 9*9 do
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nines</span><span style="color: #0000FF;">)!=</span><span style="color: #000000;">27</span> <span style="color: #008080;">then</span> <span style="color: #0000FF;">?</span><span style="color: #000000;">9</span><span style="color: #0000FF;">/</span><span style="color: #000000;">0</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
six = {}
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
nine = nines[cols[i]] -- dotcol
<span style="color: #000000;">six</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
for j=1 to length(nine) do
<span style="color: #000000;">nine</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">nines</span><span style="color: #0000FF;">[</span><span style="color: #000000;">cols</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]]</span> <span style="color: #000080;font-style:italic;">-- dotcol</span>
if squares[i]!=squares[nine[j]] then
<span style="color: #008080;">for</span> <span style="color: #000000;">j</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nine</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
six = append(six,nine[j])
<span style="color: #008080;">if</span> <span style="color: #000000;">squares</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]!=</span><span style="color: #000000;">squares</span><span style="color: #0000FF;">[</span><span style="color: #000000;">nine</span><span style="color: #0000FF;">[</span><span style="color: #000000;">j</span><span style="color: #0000FF;">]]</span> <span style="color: #008080;">then</span>
end if
<span style="color: #000000;">six</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">six</span><span style="color: #0000FF;">,</span><span style="color: #000000;">nine</span><span style="color: #0000FF;">[</span><span style="color: #000000;">j</span><span style="color: #0000FF;">])</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
ndx = find(six,sixes)
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
if ndx=0 then
<span style="color: #000000;">ndx</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">find</span><span style="color: #0000FF;">(</span><span style="color: #000000;">six</span><span style="color: #0000FF;">,</span><span style="color: #000000;">sixes</span><span style="color: #0000FF;">)</span>
sixes = append(sixes,six)
<span style="color: #008080;">if</span> <span style="color: #000000;">ndx</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
ndx = length(sixes)
<span style="color: #000000;">sixes</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">sixes</span><span style="color: #0000FF;">,</span><span style="color: #000000;">six</span><span style="color: #0000FF;">)</span>
end if
<span style="color: #000000;">ndx</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">sixes</span><span style="color: #0000FF;">)</span>
dotcol[i] = ndx
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
six = {}
<span style="color: #000000;">dotcol</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">ndx</span>
nine = nines[rows[i]] -- dotrow
<span style="color: #000000;">six</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
for j=1 to length(nine) do
<span style="color: #000000;">nine</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">nines</span><span style="color: #0000FF;">[</span><span style="color: #000000;">rows</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]]</span> <span style="color: #000080;font-style:italic;">-- dotrow</span>
if squares[i]!=squares[nine[j]] then
<span style="color: #008080;">for</span> <span style="color: #000000;">j</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nine</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
six = append(six,nine[j])
<span style="color: #008080;">if</span> <span style="color: #000000;">squares</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]!=</span><span style="color: #000000;">squares</span><span style="color: #0000FF;">[</span><span style="color: #000000;">nine</span><span style="color: #0000FF;">[</span><span style="color: #000000;">j</span><span style="color: #0000FF;">]]</span> <span style="color: #008080;">then</span>
end if
<span style="color: #000000;">six</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">six</span><span style="color: #0000FF;">,</span><span style="color: #000000;">nine</span><span style="color: #0000FF;">[</span><span style="color: #000000;">j</span><span style="color: #0000FF;">])</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
ndx = find(six,sixes)
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
if ndx=0 then
<span style="color: #000000;">ndx</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">find</span><span style="color: #0000FF;">(</span><span style="color: #000000;">six</span><span style="color: #0000FF;">,</span><span style="color: #000000;">sixes</span><span style="color: #0000FF;">)</span>
sixes = append(sixes,six)
<span style="color: #008080;">if</span> <span style="color: #000000;">ndx</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
ndx = length(sixes)
<span style="color: #000000;">sixes</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">sixes</span><span style="color: #0000FF;">,</span><span style="color: #000000;">six</span><span style="color: #0000FF;">)</span>
end if
<span style="color: #000000;">ndx</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">sixes</span><span style="color: #0000FF;">)</span>
dotrow[i] = ndx
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end for
<span style="color: #000000;">dotrow</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">ndx</span>
end procedure
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
set_nines()
<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span>
 
<span style="color: #000000;">set_nines</span><span style="color: #0000FF;">()</span>
integer improved = 0
 
<span style="color: #004080;">integer</span> <span style="color: #000000;">improved</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
function eliminate_in(sequence valid, sequence set, integer ch)
for i=1 to length(set) do
<span style="color: #008080;">function</span> <span style="color: #000000;">eliminate_in</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">set</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">ch</span><span style="color: #0000FF;">)</span>
integer idx = set[i]
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">set</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
if string(valid[idx]) then
<span style="color: #004080;">integer</span> <span style="color: #000000;">idx</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">set</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span>
integer k = find(ch,valid[idx])
<span style="color: #008080;">if</span> <span style="color: #004080;">string</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">])</span> <span style="color: #008080;">then</span>
if k!=0 then
<span style="color: #004080;">integer</span> <span style="color: #000000;">k</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">find</span><span style="color: #0000FF;">(</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">,</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">])</span>
valid[idx][k..k] = ""
<span style="color: #008080;">if</span> <span style="color: #000000;">k</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
improved = 1
<span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">][</span><span style="color: #000000;">k</span><span style="color: #0000FF;">..</span><span style="color: #000000;">k</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">""</span>
end if
<span style="color: #000000;">improved</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
return valid
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end function
<span style="color: #008080;">return</span> <span style="color: #000000;">valid</span>
 
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
function test_comb(sequence chosen, sequence pool, sequence valid)
--
<span style="color: #008080;">function</span> <span style="color: #000000;">test_comb</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">chosen</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">pool</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">valid</span><span style="color: #0000FF;">)</span>
-- (see deep_logic()/set elimination)
<span style="color: #000080;font-style:italic;">--
-- chosen is a sequence of length 2..4 of integers 1..9: ordered elements of pool.
-- (see deep_logic()/set elimination)
-- pool is a set of elements of the sequence valid, each of which is a sequence.
-- chosen is a sequence of length 2..4 of integers 1..9: ordered elements of pool.
-- (note that elements of valid in pool not in chosen are not necessarily sequences)
-- pool is a set of elements of the sequence valid, each of which is a sequence.
--
-- (note that elements of valid in pool not in chosen are not necessarily sequences)
sequence contains = repeat(0,9)
--</span>
integer ccount = 0, ch
<span style="color: #004080;">sequence</span> <span style="color: #000000;">contains</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">)</span>
object set
<span style="color: #004080;">integer</span> <span style="color: #000000;">ccount</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">ch</span>
 
<span style="color: #004080;">object</span> <span style="color: #000000;">set</span>
for i=1 to length(chosen) do
set = valid[pool[chosen[i]]]
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">chosen</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
for j=1 to length(set) do
<span style="color: #000000;">set</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">pool</span><span style="color: #0000FF;">[</span><span style="color: #000000;">chosen</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]]]</span>
ch = set[j]-'0'
<span style="color: #008080;">for</span> <span style="color: #000000;">j</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">set</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
if contains[ch]=0 then
<span style="color: #000000;">ch</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">set</span><span style="color: #0000FF;">[</span><span style="color: #000000;">j</span><span style="color: #0000FF;">]-</span><span style="color: #008000;">'0'</span>
contains[ch] = 1
<span style="color: #008080;">if</span> <span style="color: #000000;">contains</span><span style="color: #0000FF;">[</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">]=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
ccount += 1
<span style="color: #000000;">contains</span><span style="color: #0000FF;">[</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span>
end if
<span style="color: #000000;">ccount</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
if ccount=length(chosen) then
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
for i=1 to length(pool) do
<span style="color: #008080;">if</span> <span style="color: #000000;">ccount</span><span style="color: #0000FF;">=</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">chosen</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
if find(i,chosen)=0 then
<span style="color: #000000;">valid</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">deep_copy</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">)</span>
set = valid[pool[i]]
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">pool</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
if sequence(set) then
<span style="color: #008080;">if</span> <span style="color: #7060A8;">find</span><span style="color: #0000FF;">(</span><span style="color: #000000;">i</span><span style="color: #0000FF;">,</span><span style="color: #000000;">chosen</span><span style="color: #0000FF;">)=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
-- (reverse order so deletions don't foul indexes)
<span style="color: #000000;">set</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">pool</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]]</span>
for j=length(set) to 1 by -1 do
<span style="color: #008080;">if</span> <span style="color: #004080;">sequence</span><span style="color: #0000FF;">(</span><span style="color: #000000;">set</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
ch = set[j]-'0'
<span style="color: #000080;font-style:italic;">-- (reverse order so deletions don't foul indexes)</span>
if contains[ch] then
<span style="color: #008080;">for</span> <span style="color: #000000;">j</span><span style="color: #0000FF;">=</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">set</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">to</span> <span style="color: #000000;">1</span> <span style="color: #008080;">by</span> <span style="color: #0000FF;">-</span><span style="color: #000000;">1</span> <span style="color: #008080;">do</span>
valid[pool[i]][j..j] = ""
<span style="color: #000000;">ch</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">set</span><span style="color: #0000FF;">[</span><span style="color: #000000;">j</span><span style="color: #0000FF;">]-</span><span style="color: #008000;">'0'</span>
improved = 1
<span style="color: #008080;">if</span> <span style="color: #000000;">contains</span><span style="color: #0000FF;">[</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">]</span> <span style="color: #008080;">then</span>
end if
<span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">pool</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]][</span><span style="color: #000000;">j</span><span style="color: #0000FF;">..</span><span style="color: #000000;">j</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">""</span>
end for
<span style="color: #000000;">improved</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
return valid
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end function
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
 
<span style="color: #008080;">return</span> <span style="color: #000000;">valid</span>
-- from [[Combinations#Phix|Combinations]]
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
-- from http://rosettacode.org/wiki/Combinations#Phix
function comb(sequence pool, valid, integer needed, done=0, sequence chosen={})
<span style="color: #000080;font-style:italic;">-- from [[Combinations#Phix|Combinations]]
-- (used by deep_logic()/set elimination)
-- from http://rosettacode.org/wiki/Combinations#Phix</span>
if needed=0 then -- got a full set
<span style="color: #008080;">function</span> <span style="color: #000000;">comb</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">pool</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">needed</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">done</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">sequence</span> <span style="color: #000000;">chosen</span><span style="color: #0000FF;">={})</span>
return test_comb(chosen,pool,valid)
<span style="color: #000080;font-style:italic;">-- (used by deep_logic()/set elimination)</span>
end if
<span style="color: #008080;">if</span> <span style="color: #000000;">needed</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span> <span style="color: #000080;font-style:italic;">-- got a full set</span>
if done+needed>length(pool) then return valid end if -- cannot fulfil
<span style="color: #008080;">return</span> <span style="color: #000000;">test_comb</span><span style="color: #0000FF;">(</span><span style="color: #000000;">chosen</span><span style="color: #0000FF;">,</span><span style="color: #000000;">pool</span><span style="color: #0000FF;">,</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">)</span>
-- get all combinations with and without the next item:
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
done += 1
<span style="color: #008080;">if</span> <span style="color: #000000;">done</span><span style="color: #0000FF;">+</span><span style="color: #000000;">needed</span><span style="color: #0000FF;">></span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">pool</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #000000;">valid</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #000080;font-style:italic;">-- cannot fulfil
if sequence(valid[pool[done]]) then
-- get all combinations with and without the next item:</span>
valid = comb(pool,valid,needed-1,done,append(chosen,done))
<span style="color: #000000;">done</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span>
end if
<span style="color: #008080;">if</span> <span style="color: #004080;">sequence</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">pool</span><span style="color: #0000FF;">[</span><span style="color: #000000;">done</span><span style="color: #0000FF;">]])</span> <span style="color: #008080;">then</span>
return comb(pool,valid,needed,done,chosen)
<span style="color: #000000;">valid</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">comb</span><span style="color: #0000FF;">(</span><span style="color: #000000;">pool</span><span style="color: #0000FF;">,</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span><span style="color: #000000;">needed</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">done</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">deep_copy</span><span style="color: #0000FF;">(</span><span style="color: #000000;">chosen</span><span style="color: #0000FF;">),</span><span style="color: #000000;">done</span><span style="color: #0000FF;">))</span>
end function
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
 
<span style="color: #008080;">return</span> <span style="color: #000000;">comb</span><span style="color: #0000FF;">(</span><span style="color: #000000;">pool</span><span style="color: #0000FF;">,</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span><span style="color: #000000;">needed</span><span style="color: #0000FF;">,</span><span style="color: #000000;">done</span><span style="color: #0000FF;">,</span><span style="color: #000000;">chosen</span><span style="color: #0000FF;">)</span>
function deep_logic(string board, sequence valid)
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
--
-- Create a grid of valid moves. Note this does not modify board, but instead creates
<span style="color: #008080;">function</span> <span style="color: #000000;">deep_logic</span><span style="color: #0000FF;">(</span><span style="color: #004080;">string</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">sequence</span> <span style="color: #000000;">valid</span><span style="color: #0000FF;">)</span>
-- sets of permitted values for each cell, which can also be and are used for hints.
<span style="color: #000080;font-style:italic;">--
-- Apply standard eliminations of known cells, then try some more advanced tactics:
-- Create a grid of valid moves. Note this does not modify board, but instead creates
--
-- sets of permitted values for each cell, which can also be and are used for hints.
-- 1) row/col elimination
-- Apply standard eliminations of known cells, then try some more advanced tactics:
-- If in any of the 9 small squares a number can only occur in one row or column,
--
-- then that number cannot occur in that row or column in two other corresponding
-- 1) row/col elimination
-- small squares. Example (this one with significant practical benefit):
-- If in any of the 9 small squares a number can only occur in one row or column,
-- 000|000|036
-- then that number cannot occur in that row or column in two other corresponding
-- 840|000|000
-- small squares. Example (this one with significant practical benefit):
-- 000|000|020
-- ---+---+---000|000|036
-- 000840|203000|000
-- 010000|000|700020
-- 000|600|400---+---+---
-- ---+---+---000|203|000
-- 000010|410000|050700
-- 003|000|200600|400
-- 600|000|000 <-- 3-+---+---
-- ^-- 3000|410|050
-- 003|000|200
-- Naively, the br can contain a 3 in the four corners, but looking at mid-right and
-- 600|000|000 &lt;-- 3
-- mid-bottom leads us to eliminating 3s in column 9 and row 9, leaving 7,7 as the
-- only square in the br that can be a 3. Uses dotcol and dotrow. ^-- 3
-- Without thisNaively, brutethe forcebr oncan thecontain abovea takes3 ~8sin the four corners, but withlooking itat mid-right ~0sand
-- mid-bottom leads us to eliminating 3s in column 9 and row 9, leaving 7,7 as the
--
-- only square in the br that can be a 3. Uses dotcol and dotrow.
-- 2) set elimination
-- Without this, brute force on the above takes ~8s, but with it ~0s
-- If in any 9-set there is a set of n blank squares that can only contain n digits,
--
-- then no other squares can contain those digits. Example (with some benefit):
-- 2) set elimination
-- 75.|.9.|.46
-- If in any 9-set there is a set of n blank squares that can only contain n digits,
-- 961|...|352
-- then no other squares can contain those digits. Example (with some benefit):
-- 4..|...|79.
-- ---+---+---75.|.9.|.46
-- 2961|..|6.1|..7352
-- 4.8.|...|.279.
-- 1..|328|.65---+---+---
-- ---+---+---2..|6.1|..7
-- ..8.|...|.2.. <-- [7,8] is {1,3,8}, [7,9] is {1,3,8}
-- 3.9|.1..|2328|.4 <-- [8,8] is {1,8}65
-- 84.|.3.|.79---+---+---
-- The three cells above the br 479 can only...|...|... &lt;-- [7,8] containis {1,3,8}, so[7,9] the .. of the .2.is {1,3,8}
-- in column 7 of that square are {5,6} (not3.9|...|2.4 1) and hence &lt;-- [98,48] must be ais {1.,8}
-- 84.|.3.|.79
-- (Relies on plain_logic to spot that "must be a 1", and serves as a clear example
-- The ofthree whycells thisabove routinethe shouldbr not479 bothercan toonly attemptcontain updating{1,3,8}, so the board.. itselfof -the .2. as
-- in itcolumn spends7 almostof allthat ofsquare itsare time{5,6} looking(not in1) aand completelyhence different[9,4] placemust be a 1.)
-- (OneRelies couldon argueplain_logic to spot that [7,7]"must andbe [9a 1",7] areand theserves onlyas placesa thatclear canexample hold {5,6} and
-- thereforeof wewhy this routine should eliminatenot allbother non-{5,6}to fromattempt thoseupdating squares,the asboard anitself alternative- as
-- it spends almost all of its time looking in a completely different place.)
-- strategy. However I think that would be harder to code and cannot imagine a case
-- (One saidcould complementaryargue logicthat covers[7,7] thatand [9,7] are the aboveonly places that can doeshold not{5,6} cmiiw.)and
-- therefore we should eliminate all non-{5,6} from those squares, as an alternative
--
-- strategy. However I think that would be harder to code and cannot imagine a case
-- 3) x-wings
-- said complementary logic covers, that the above does not, cmiiw.)
-- If a pair of rows or columns can only contain a given number in two matching places,
--
-- then once filled they will occupy opposite diagonal corners, hence that said number
-- 3) x-wings
-- cannot occur elsewhere in those two columns/rows. Example (with a benefit):
-- If a pair of rows or columns can .43|98.|25.only <--contain 6a given number in [1,{6two matching places,9}]
-- then once filled they will occupy opposite diagonal corners, hence that said number
-- 6..|425|...
-- cannot occur elsewhere in those two columns/rows. Example (with a benefit):
-- 2..|..1|.94
-- .43|98.|25. &lt;---+---+--- 6 in [1,{6,9}]
-- 96..|425|..4|.7. <-- hence 6 not in [4,9]
-- 32..|6.8.1|...94
-- 41.|2.9|..3---+---+---
-- 9..|..4|.7. &lt;---+---+--- hence 6 not in [4,9]
-- 823..|5.6.8|... <-- hence 6 not in [7,6],[7,9]
-- ..41.|2.4.9|..5 <-- hence 6 not in [8,6]3
-- 534|89.|71. <-- 6 in [9,{6,9}]-+---+---
-- A 6 must be in [1,6] or [1,9] and82.|5..|... [9,6] or [9,9], hence [7,9] is not 6 and must be &lt;-- hence 6 not in [7,6],[7,9.]
-- ...|.4.|..5 &lt;-- hence 6 not in [8,6]
-- (we also eliminate 6 from [4,9], [7,6] and [8,6] to no great use)
-- In practice this offers little benefit over a single534|89.|71. trial&lt;-and-error step,6 asin [9,{6,9}]
-- A obviously6 tryingmust either 6be in row [1,6] or [1,9] immediatelyand pinpoints[9,6] thator [9,9], anywayhence [7,9] is not 6 and must be 9.
-- (we also eliminate 6 from [4,9], [7,6] and [8,6] to no great use)
--
-- In practice this offers little benefit over a single trial-and-error step, as
-- 4) swordfish (not attempted)
-- obviously trying either 6 in row 1 or 9 immediately pinpoints that 9 anyway.
-- There is an extension to x-wings known as swordfish: three (or more) pairs form
--
-- a staggered pair (or more) of rectangles that exhibit similar properties, eg:
-- 4) swordfish (not attempted)
-- 8-1|-5-|-3-
-- There is an extension to x-wings known as swordfish: three (or more) pairs form
-- 953|-68|---
-- a staggered pair (or more) of rectangles that exhibit similar properties, eg:
-- -4-|-*3|5*8
-- 8-1|-5-+---+-|-3-
-- 6--953|9-268|---
-- -84-|-*3-|-4-5*8
-- 3*-|5-1|-*7 <+---+--- hence [6,3] is not 9, must be 4
-- 6--|9-+---+2|---
-- 5*2-8-|-*3-|-84-
-- 3*--8|375-1|-*7 &lt;-- hence [6,3] is not 9, must be 4
-- -3-|82-|1+---+---
-- ^5*2|-*-|-^8---^-- 3 pairs of 9s (marked with *) on 3 rows (only)
-- --8|37-|--9
-- It is not a swordfish if the 3 pairs are on >3 rows, I trust that is obvious.
-- -3-|82-|1--
-- Logically you can extend this to N pairs on N rows, however I cannot imagine a
-- ^---^---^-- 3 pairs of 9s (marked with *) on 3 rows (only)
-- case where this is not immediately solved by a single trial-step being invalid.
-- (egIt aboveis ifnot youa tryswordfish [3,5]:=9if itthe is3 quicklypairs provedare toon be&gt;3 invalidrows, andI thetrust that is sameobvious.
-- Logically you can extend this to N pairs on N rows, however I cannot imagine a
-- goes for [6,8]:=9 and [7,2]:=9, since they are all entirely inter-dependent.)
-- Obviouslycase where Ithis haveis saidnot rows,immediately thesolved sameby concepta cansingle be appliedtrial-step tobeing columnsinvalid.
-- (eg above if you try [3,5]:=9 it is quickly proved to be invalid, and the same
-- Likewise there are "Alternate Pairs" and "Hook or X-Y wing" strategies, which
-- goes for [6,8]:=9 and [7,2]:=9, since they are all entirely inter-dependent.)
-- are easily solved with a single trial-and-error step, and of course the brute
-- forceObviously algorithmwhere isI goinghave tosaid selectrows, pairsthe firstsame anyway.concept [Erm,can nobe itapplied doesn't,to columns.
-- Likewise there are "Alternate Pairs" and "Hook or X-Y wing" strategies, which
-- it selects shortest - I've noted the possible improvement below.]
-- are easily solved with a single trial-and-error step, and of course the brute
--
-- force algorithm is going to select pairs first anyway. [Erm, no it doesn't,
integer col, row
-- it selects shortest - I've noted the possible improvement below.]
sequence c, r
--</span>
sequence nine, prevsets, set
<span style="color: #004080;">integer</span> <span style="color: #000000;">k</span> <span style="color: #000080;font-style:italic;">-- (scratch)</span>
object vj
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">)=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
integer ch, k, idx, sx, sy, count
<span style="color: #000080;font-style:italic;">-- initialise/start again from scratch</span>
 
<span style="color: #000000;">valid</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"123456789"</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span><span style="color: #0000FF;">)</span>
if length(valid)=0 then
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
-- initialise/start again from scratch
<span style="color: #000080;font-style:italic;">--
valid = repeat("123456789",9*9)
-- First perform standard eliminations of any known cells:
end if
-- (repeated every time so plain_logic() does not have to worry about it)
--
--</span>
-- First perform standard eliminations of any known cells:
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
-- (repeated every time so plain_logic() does not have to worry about it)
<span style="color: #004080;">integer</span> <span style="color: #000000;">ch</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span>
--
<span style="color: #008080;">if</span> <span style="color: #000000;">ch</span><span style="color: #0000FF;">></span><span style="color: #008000;">'0'</span>
for i=1 to 9*9 do
<span style="color: #008080;">and</span> <span style="color: #004080;">string</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">])</span> <span style="color: #008080;">then</span>
ch = board[i]
<span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">ch</span>
if ch>'0'
<span style="color: #000000;">valid</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">eliminate_in</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span><span style="color: #000000;">nines</span><span style="color: #0000FF;">[</span><span style="color: #000000;">cols</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]],</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">)</span>
and string(valid[i]) then
<span style="color: #000000;">valid</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">eliminate_in</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span><span style="color: #000000;">nines</span><span style="color: #0000FF;">[</span><span style="color: #000000;">rows</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]],</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">)</span>
valid[i] = ch
<span style="color: #000000;">valid</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">eliminate_in</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span><span style="color: #000000;">nines</span><span style="color: #0000FF;">[</span><span style="color: #000000;">squares</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]],</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">)</span>
valid = eliminate_in(valid,nines[cols[i]],ch)
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
valid = eliminate_in(valid,nines[rows[i]],ch)
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
valid = eliminate_in(valid,nines[squares[i]],ch)
<span style="color: #000080;font-style:italic;">--
end if
-- 1) row/col elimination
end for
--</span>
<span style="color: #008080;">for</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">=</span><span style="color: #000000;">19</span> <span style="color: #008080;">to</span> <span style="color: #000000;">27</span> <span style="color: #008080;">do</span>
-- 1) row/col elimination
<span style="color: #004080;">sequence</span> <span style="color: #000000;">c</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">),</span> <span style="color: #000080;font-style:italic;">-- 0 = none seen, 1..9 this col only, -1: &gt;1 col</span>
--
<span style="color: #000000;">r</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">),</span> <span style="color: #000080;font-style:italic;">-- "" row row</span>
for s=19 to 27 do
<span style="color: #000000;">nine</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">nines</span><span style="color: #0000FF;">[</span><span style="color: #000000;">s</span><span style="color: #0000FF;">]</span>
c = repeat(0,9) -- 0 = none seen, 1..9 this col only, -1: >1 col
<span style="color: #004080;">integer</span> <span style="color: #000000;">row</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">col</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">ch</span>
r = repeat(0,9) -- "" row row
<span style="color: #008080;">for</span> <span style="color: #000000;">n</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
nine = nines[s]
<span style="color: #000000;">k</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">nine</span><span style="color: #0000FF;">[</span><span style="color: #000000;">n</span><span style="color: #0000FF;">]</span>
for n=1 to 9 do
<span style="color: #004080;">object</span> <span style="color: #000000;">vk</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">k</span><span style="color: #0000FF;">]</span>
k = nine[n]
<span style="color: #008080;">if</span> <span style="color: #004080;">string</span><span style="color: #0000FF;">(</span><span style="color: #000000;">vk</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
vj = valid[k]
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">vk</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
if string(vj) then
<span style="color: #000000;">ch</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">vk</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]-</span><span style="color: #008000;">'0'</span>
for i=1 to length(vj) do
<span style="color: #000000;">col</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">dotcol</span><span style="color: #0000FF;">[</span><span style="color: #000000;">k</span><span style="color: #0000FF;">]</span>
ch = vj[i]-'0'
<span style="color: #000000;">row</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">dotrow</span><span style="color: #0000FF;">[</span><span style="color: #000000;">k</span><span style="color: #0000FF;">]</span>
col = dotcol[k]
<span style="color: #000000;">c</span><span style="color: #0000FF;">[</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #008080;">iff</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">find</span><span style="color: #0000FF;">(</span><span style="color: #000000;">c</span><span style="color: #0000FF;">[</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">],{</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">col</span><span style="color: #0000FF;">})!=</span><span style="color: #000000;">0</span><span style="color: #0000FF;">?</span><span style="color: #000000;">col</span><span style="color: #0000FF;">:-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span>
row = dotrow[k]
<span style="color: #000000;">r</span><span style="color: #0000FF;">[</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #008080;">iff</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">find</span><span style="color: #0000FF;">(</span><span style="color: #000000;">r</span><span style="color: #0000FF;">[</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">],{</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">row</span><span style="color: #0000FF;">})!=</span><span style="color: #000000;">0</span><span style="color: #0000FF;">?</span><span style="color: #000000;">row</span><span style="color: #0000FF;">:-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span>
c[ch] = iff(find(c[ch],{0,col})!=0?col:-1)
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
r[ch] = iff(find(r[ch],{0,row})!=0?row:-1)
<span style="color: #008080;">end</span> <span style="color: for#008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end if
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
end for
<span style="color: #000000;">ch</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">+</span><span style="color: #008000;">'0'</span>
for i=1 to 9 do
<span style="color: #000000;">col</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">c</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span>
ch = i+'0'
<span style="color: #008080;">if</span> <span style="color: #000000;">col</span><span style="color: #0000FF;">></span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
col = c[i]
<span style="color: #000000;">valid</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">eliminate_in</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span><span style="color: #000000;">sixes</span><span style="color: #0000FF;">[</span><span style="color: #000000;">col</span><span style="color: #0000FF;">],</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">)</span>
if col>0 then
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
valid = eliminate_in(valid,sixes[col],ch)
<span style="color: #000000;">row</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">r</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span>
end if
<span style="color: #008080;">if</span> <span style="color: #000000;">row</span><span style="color: #0000FF;">></span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
row = r[i]
<span style="color: #000000;">valid</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">eliminate_in</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span><span style="color: #000000;">sixes</span><span style="color: #0000FF;">[</span><span style="color: #000000;">row</span><span style="color: #0000FF;">],</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">)</span>
if row>0 then
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
valid = eliminate_in(valid,sixes[row],ch)
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #000080;font-style:italic;">--
end for
-- 2) set elimination
-- 2) set elimination</span>
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nines</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
--
<span style="color: #000080;font-style:italic;">--
for i=1 to length(nines) do
-- Practical note: Meticulously counting empties to eliminate larger set sizes
--
-- would at best reduce 6642 tests to 972, not deemed worth it.
-- Practical note: Meticulously counting empties to eliminate larger set sizes
--</span>
-- would at best reduce 6642 tests to 972, not deemed worth it.
<span style="color: #008080;">for</span> <span style="color: #000000;">set_size</span><span style="color: #0000FF;">=</span><span style="color: #000000;">2</span> <span style="color: #008080;">to</span> <span style="color: #000000;">4</span> <span style="color: #008080;">do</span>
--
<span style="color: #000080;font-style:italic;">--if floor(count_empties(nines[i])/2)&gt;=set_size then -- (untested)</span>
for set_size=2 to 4 do
<span style="color: #000000;">valid</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">comb</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nines</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">],</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span><span style="color: #000000;">set_size</span><span style="color: #0000FF;">)</span>
--if floor(count_empties(nines[i])/2)>=set_size then -- (untested)
<span style="color: #000080;font-style:italic;">--end if</span>
valid = comb(nines[i],valid,set_size)
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
--end if
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #000080;font-style:italic;">--
end for
-- 3) x-wings
-- 3) x-wings</span>
<span style="color: #008080;">for</span> <span style="color: #000000;">ch</span><span style="color: #0000FF;">=</span><span style="color: #008000;">'1'</span> <span style="color: #008080;">to</span> <span style="color: #008000;">'9'</span> <span style="color: #008080;">do</span>
--
<span style="color: #004080;">sequence</span> <span style="color: #000000;">prevsets</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">),</span> <span style="color: #000000;">set</span>
for ch='1' to '9' do
<span style="color: #004080;">integer</span> <span style="color: #000000;">count</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">idx</span>
prevsets = repeat(0,9)
<span style="color: #008080;">for</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
for x=1 to 9 do
<span style="color: #000000;">count</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
count = 0
<span style="color: #000000;">set</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">)</span>
set = repeat(0,9)
<span style="color: #008080;">for</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">to</span> <span style="color: #000000;">8</span> <span style="color: #008080;">do</span>
for y=0 to 8 do
<span style="color: #000000;">idx</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span><span style="color: #0000FF;">+</span><span style="color: #000000;">x</span>
idx = y*9+x
<span style="color: #008080;">if</span> <span style="color: #004080;">sequence</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">])</span> <span style="color: #008080;">and</span> <span style="color: #7060A8;">find</span><span style="color: #0000FF;">(</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">,</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">])</span> <span style="color: #008080;">then</span>
if sequence(valid[idx]) and find(ch,valid[idx]) then
<span style="color: #000000;">set</span><span style="color: #0000FF;">[</span><span style="color: #000000;">y</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span>
set[y+1] = 1
<span style="color: #000000;">count</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">count</span><span style="color: #0000FF;">=</span><span style="color: #000000;">2</span> <span style="color: #008080;">then</span>
if count=2 then
<span style="color: #000000;">k</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">find</span><span style="color: #0000FF;">(</span><span style="color: #000000;">set</span><span style="color: #0000FF;">,</span><span style="color: #000000;">prevsets</span><span style="color: #0000FF;">)</span>
k = find(set,prevsets)
<span style="color: #008080;">if</span> <span style="color: #000000;">k</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
if k!=0 then
<span style="color: #008080;">for</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">to</span> <span style="color: #000000;">8</span> <span style="color: #008080;">do</span>
for y=0 to 8 do
<span style="color: #008080;">if</span> <span style="color: #000000;">set</span><span style="color: #0000FF;">[</span><span style="color: #000000;">y</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]=</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span>
if set[y+1]=1 then
<span style="color: #008080;">for</span> <span style="color: #000000;">sx</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
for sx=1 to 9 do
<span style="color: #008080;">if</span> <span style="color: #000000;">sx</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">k</span> <span style="color: #008080;">and</span> <span style="color: #000000;">sx</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">x</span> <span style="color: #008080;">then</span>
if sx!=k and sx!=x then
<span style="color: #000000;">valid</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">eliminate_in</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">y</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span><span style="color: #0000FF;">+</span><span style="color: #000000;">sx</span><span style="color: #0000FF;">},</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">)</span>
valid = eliminate_in(valid,{y*9+sx},ch)
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #008080;">else</span>
<span style="color: #000000;">prevsets</span><span style="color: #0000FF;">[</span><span style="color: #000000;">x</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">set</span>
prevsets[x] = set
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #000000;">prevsets</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">)</span>
prevsets = repeat(0,9)
<span style="color: #008080;">for</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">to</span> <span style="color: #000000;">8</span> <span style="color: #008080;">do</span>
for y=0 to 8 do
<span style="color: #000000;">count</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
count = 0
<span style="color: #000000;">set</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">)</span>
set = repeat(0,9)
<span style="color: #008080;">for</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
for x=1 to 9 do
<span style="color: #000000;">idx</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span><span style="color: #0000FF;">+</span><span style="color: #000000;">x</span>
idx = y*9+x
<span style="color: #008080;">if</span> <span style="color: #004080;">sequence</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">])</span> <span style="color: #008080;">and</span> <span style="color: #7060A8;">find</span><span style="color: #0000FF;">(</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">,</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">])</span> <span style="color: #008080;">then</span>
if sequence(valid[idx]) and find(ch,valid[idx]) then
<span style="color: #000000;">set</span><span style="color: #0000FF;">[</span><span style="color: #000000;">x</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span>
set[x] = 1
<span style="color: #000000;">count</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">count</span><span style="color: #0000FF;">=</span><span style="color: #000000;">2</span> <span style="color: #008080;">then</span>
if count=2 then
<span style="color: #000000;">k</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">find</span><span style="color: #0000FF;">(</span><span style="color: #000000;">set</span><span style="color: #0000FF;">,</span><span style="color: #000000;">prevsets</span><span style="color: #0000FF;">)</span>
k = find(set,prevsets)
<span style="color: #008080;">if</span> <span style="color: #000000;">k</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
if k!=0 then
<span style="color: #008080;">for</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
for x=1 to 9 do
<span style="color: #008080;">if</span> <span style="color: #000000;">set</span><span style="color: #0000FF;">[</span><span style="color: #000000;">x</span><span style="color: #0000FF;">]=</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span>
if set[x]=1 then
<span style="color: #008080;">for</span> <span style="color: #000000;">sy</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">to</span> <span style="color: #000000;">8</span> <span style="color: #008080;">do</span>
for sy=0 to 8 do
<span style="color: #008080;">if</span> <span style="color: #000000;">sy</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">k</span> <span style="color: #008080;">and</span> <span style="color: #000000;">sy</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">y</span> <span style="color: #008080;">then</span>
if sy+1!=k and sy!=y then
<span style="color: #000000;">valid</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">eliminate_in</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">sy</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span><span style="color: #0000FF;">+</span><span style="color: #000000;">x</span><span style="color: #0000FF;">},</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">)</span>
valid = eliminate_in(valid,{sy*9+x},ch)
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #008080;">else</span>
<span style="color: #000000;">prevsets</span><span style="color: #0000FF;">[</span><span style="color: #000000;">y</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">set</span>
prevsets[y+1] = set
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #008080;">return</span> <span style="color: #000000;">valid</span>
return valid
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
end function
 
<span style="color: #008080;">function</span> <span style="color: #000000;">permitted_in</span><span style="color: #0000FF;">(</span><span style="color: #004080;">string</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">sequence</span> <span style="color: #000000;">sets</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">ch</span><span style="color: #0000FF;">)</span>
function permitted_in(string board, sequence sets, sequence valid, integer ch)
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
sequence set
<span style="color: #004080;">sequence</span> <span style="color: #000000;">set</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">nines</span><span style="color: #0000FF;">[</span><span style="color: #000000;">sets</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]]</span>
integer pos, idx, bch
<span style="color: #004080;">integer</span> <span style="color: #000000;">pos</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
for i=1 to 9 do
<span style="color: #008080;">for</span> <span style="color: #000000;">j</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
set = nines[sets[i]]
<span style="color: #004080;">integer</span> <span style="color: #000000;">idx</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">set</span><span style="color: #0000FF;">[</span><span style="color: #000000;">j</span><span style="color: #0000FF;">],</span>
pos = 0
<span style="color: #000000;">bch</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">]</span>
for j=1 to 9 do
<span style="color: #008080;">if</span> <span style="color: #000000;">bch</span><span style="color: #0000FF;">></span><span style="color: #008000;">'0'</span> <span style="color: #008080;">then</span>
idx = set[j]
<span style="color: #008080;">if</span> <span style="color: #000000;">bch</span><span style="color: #0000FF;">=</span><span style="color: #000000;">ch</span> <span style="color: #008080;">then</span> <span style="color: #000000;">pos</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">-</span><span style="color: #000000;">1</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
bch = board[idx]
<span style="color: #008080;">elsif</span> <span style="color: #7060A8;">find</span><span style="color: #0000FF;">(</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">,</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">idx</span><span style="color: #0000FF;">])</span> <span style="color: #008080;">then</span>
if bch>'0' then
<span style="color: #008080;">if</span> <span style="color: #000000;">pos</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span> <span style="color: #000000;">pos</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">-</span><span style="color: #000000;">1</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
if bch=ch then pos = -1 exit end if
<span style="color: #000000;">pos</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">idx</span>
elsif find(ch,valid[idx]) then
<span if pos!style=0"color: then#008080;">end</span> pos<span style="color: -1 exit end #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
pos = idx
<span style="color: #008080;">if</span> <span style="color: #000000;">pos</span><span style="color: #0000FF;">></span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
end if
<span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">pos</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">ch</span>
end for
<span style="color: #000000;">improved</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span>
if pos>0 then
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
board[pos] = ch
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
improved = 1
<span style="color: #008080;">return</span> <span style="color: #000000;">board</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
end for
return board
<span style="color: #008080;">enum</span> <span style="color: #000000;">INVALID</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">INCOMPLETE</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">SOLVED</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">MULTIPLE</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">2</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">BRUTE</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">3</span>
end function
 
<span style="color: #008080;">function</span> <span style="color: #000000;">plain_logic</span><span style="color: #0000FF;">(</span><span style="color: #004080;">string</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">)</span>
enum INVALID = -1, INCOMPLETE = 0, SOLVED = 1, MULTIPLE = 2, BRUTE = 3
<span style="color: #000080;font-style:italic;">--
 
-- Responsible for:
function plain_logic(string board)
-- 1) cells with only one option
--
-- 2) numbers with only one home
-- Responsible for:
--</span>
-- 1) cells with only one option
<span style="color: #004080;">integer</span> <span style="color: #000000;">solved</span>
-- 2) numbers with only one home
<span style="color: #004080;">sequence</span> <span style="color: #000000;">valid</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
--
<span style="color: #008080;">while</span> <span style="color: #004600;">true</span> <span style="color: #008080;">do</span>
integer solved
<span style="color: #000000;">solved</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">SOLVED</span>
sequence valid = {}
<span style="color: #000000;">improved</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
object vi
<span style="color: #000000;">valid</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">deep_logic</span><span style="color: #0000FF;">(</span><span style="color: #000000;">board</span><span style="color: #0000FF;">,</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">)</span>
 
while 1 do
<span style="color: #000080;font-style:italic;">-- 1) cells with only one option:</span>
solved = SOLVED
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
improved = 0
<span style="color: #004080;">object</span> <span style="color: #000000;">vi</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span>
valid = deep_logic(board,valid)
<span style="color: #008080;">if</span> <span style="color: #004080;">string</span><span style="color: #0000FF;">(</span><span style="color: #000000;">vi</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
 
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">vi</span><span style="color: #0000FF;">)=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">board</span><span style="color: #0000FF;">,{},</span><span style="color: #000000;">INVALID</span><span style="color: #0000FF;">}</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
-- 1) cells with only one option:
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">vi</span><span style="color: #0000FF;">)=</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span>
for i=1 to length(valid) do
<span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">vi</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span>
vi = valid[i]
<span style="color: #000000;">improved</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span>
if string(vi) then
if length(vi)<span style=0"color: then#008080;">end</span> return<span {board,{},INVALID} endstyle="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
if length(vi)=1 then
<span style="color: #008080;">if</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]<=</span><span style="color: #008000;">'0'</span> <span style="color: #008080;">then</span>
board[i] = vi[1]
<span style="color: #000000;">solved</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">INCOMPLETE</span>
improved = 1
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end if
<span style="color: #008080;">if</span> <span style="color: #000000;">solved</span><span style="color: #0000FF;">=</span><span style="color: #000000;">SOLVED</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">board</span><span style="color: #0000FF;">,{},</span><span style="color: #000000;">SOLVED</span><span style="color: #0000FF;">}</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
if board[i]<='0' then
solved = INCOMPLETE
<span style="color: #000080;font-style:italic;">-- 2) numbers with only one home</span>
end if
<span style="color: #008080;">for</span> <span style="color: #000000;">ch</span><span style="color: #0000FF;">=</span><span style="color: #008000;">'1'</span> <span style="color: #008080;">to</span> <span style="color: #008000;">'9'</span> <span style="color: #008080;">do</span>
end for
<span style="color: #000000;">board</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">permitted_in</span><span style="color: #0000FF;">(</span><span style="color: #000000;">board</span><span style="color: #0000FF;">,</span><span style="color: #000000;">cols</span><span style="color: #0000FF;">,</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">)</span>
if solved=SOLVED then return {board,{},SOLVED} end if
<span style="color: #000000;">board</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">permitted_in</span><span style="color: #0000FF;">(</span><span style="color: #000000;">board</span><span style="color: #0000FF;">,</span><span style="color: #000000;">rows</span><span style="color: #0000FF;">,</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">)</span>
 
<span style="color: #000000;">board</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">permitted_in</span><span style="color: #0000FF;">(</span><span style="color: #000000;">board</span><span style="color: #0000FF;">,</span><span style="color: #000000;">squares</span><span style="color: #0000FF;">,</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">)</span>
-- 2) numbers with only one home
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
for ch='1' to '9' do
<span style="color: #008080;">if</span> <span style="color: #008080;">not</span> <span style="color: #000000;">improved</span> <span style="color: #008080;">then</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
board = permitted_in(board,cols,valid,ch)
<span style="color: #008080;">end</span> <span style="color: #008080;">while</span>
board = permitted_in(board,rows,valid,ch)
<span style="color: #008080;">return</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">board</span><span style="color: #0000FF;">,</span><span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span><span style="color: #000000;">solved</span><span style="color: #0000FF;">}</span>
board = permitted_in(board,squares,valid,ch)
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
end for
if not improved then exit end if
<span style="color: #008080;">function</span> <span style="color: #000000;">validate</span><span style="color: #0000FF;">(</span><span style="color: #004080;">string</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">)</span>
end while
<span style="color: #000080;font-style:italic;">-- (sum9 should be sufficient - if you want, get rid of nine/nines)</span>
return {board,valid,solved}
<span style="color: #004080;">integer</span> <span style="color: #000000;">ch</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">sum9</span>
end function
<span style="color: #004080;">sequence</span> <span style="color: #000000;">nine</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">nines</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">tagset</span><span style="color: #0000FF;">(</span><span style="color: #000000;">9</span><span style="color: #0000FF;">)</span>
 
function validate(string board)
<span style="color: #008080;">for</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">to</span> <span style="color: #000000;">8</span> <span style="color: #008080;">do</span> <span style="color: #000080;font-style:italic;">-- columns</span>
-- (sum9 should be sufficient - if you want, get rid of nine/nines)
<span style="color: #000000;">sum9</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
integer ch, sum9
<span style="color: #000000;">nine</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">)</span>
sequence nine, nines = tagset(9)
<span style="color: #008080;">for</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">81</span> <span style="color: #008080;">by</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
 
<span style="color: #000000;">ch</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">y</span><span style="color: #0000FF;">+</span><span style="color: #000000;">x</span><span style="color: #0000FF;">]-</span><span style="color: #008000;">'0'</span>
for x=0 to 8 do -- columns
<span style="color: #008080;">if</span> <span style="color: #000000;">ch</span><span style="color: #0000FF;"><</span><span style="color: #000000;">1</span> <span style="color: #008080;">or</span> <span style="color: #000000;">ch</span><span style="color: #0000FF;">></span><span style="color: #000000;">9</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #004600;">false</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
sum9 = 0
<span style="color: #000000;">sum9</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">ch</span>
nine = repeat(0,9)
<span style="color: #000000;">nine</span><span style="color: #0000FF;">[</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">ch</span>
for y=1 to 81 by 9 do
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
ch = board[y+x]-'0'
<span style="color: #008080;">if</span> <span style="color: #000000;">sum9</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">45</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #004600;">false</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
if ch<1 or ch>9 then return 0 end if
<span style="color: #008080;">if</span> <span style="color: #000000;">nine</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">nines</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #004600;">false</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
sum9 += ch
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
nine[ch] = ch
<span style="color: #008080;">for</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">81</span> <span style="color: #008080;">by</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span> <span style="color: #000080;font-style:italic;">-- rows</span>
end for
<span style="color: #000000;">sum9</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
if sum9!=45 then return 0 end if
<span style="color: #000000;">nine</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">)</span>
if nine!=nines then return 0 end if
<span style="color: #008080;">for</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">to</span> <span style="color: #000000;">8</span> <span style="color: #008080;">do</span>
end for
<span style="color: #000000;">ch</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">y</span><span style="color: #0000FF;">+</span><span style="color: #000000;">x</span><span style="color: #0000FF;">]-</span><span style="color: #008000;">'0'</span>
for y=1 to 81 by 9 do -- rows
<span style="color: #000000;">sum9</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">ch</span>
sum9 = 0
<span style="color: #000000;">nine</span><span style="color: #0000FF;">[</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">ch</span>
nine = repeat(0,9)
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
for x=0 to 8 do
<span style="color: #008080;">if</span> <span style="color: #000000;">sum9</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">45</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #004600;">false</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
ch = board[y+x]-'0'
<span style="color: #008080;">if</span> <span style="color: #000000;">nine</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">nines</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #004600;">false</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
sum9 += ch
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
nine[ch] = ch
<span style="color: #008080;">for</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">to</span> <span style="color: #000000;">8</span> <span style="color: #008080;">by</span> <span style="color: #000000;">3</span> <span style="color: #008080;">do</span> <span style="color: #000080;font-style:italic;">-- small squares</span>
end for
<span style="color: #008080;">for</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">to</span> <span style="color: #000000;">8</span> <span style="color: #008080;">by</span> <span style="color: #000000;">3</span> <span style="color: #008080;">do</span>
if sum9!=45 then return 0 end if
<span style="color: #000000;">sum9</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
if nine!=nines then return 0 end if
<span style="color: #000000;">nine</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">9</span><span style="color: #0000FF;">)</span>
end for
<span style="color: #008080;">for</span> <span style="color: #000000;">sy</span><span style="color: #0000FF;">=</span><span style="color: #000000;">y</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span> <span style="color: #008080;">to</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span><span style="color: #0000FF;">+</span><span style="color: #000000;">18</span> <span style="color: #008080;">by</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
for y=0 to 8 by 3 do -- small squares
<span style="color: #008080;">for</span> <span style="color: #000000;">sx</span><span style="color: #0000FF;">=</span><span style="color: #000000;">x</span> <span style="color: #008080;">to</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">+</span><span style="color: #000000;">2</span> <span style="color: #008080;">do</span>
for x=0 to 8 by 3 do
<span style="color: #000000;">ch</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">sy</span><span style="color: #0000FF;">+</span><span style="color: #000000;">sx</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]-</span><span style="color: #008000;">'0'</span>
sum9 = 0
<span style="color: #000000;">sum9</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">ch</span>
nine = repeat(0,9)
<span style="color: #000000;">nine</span><span style="color: #0000FF;">[</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">ch</span>
for sy=y*9 to y*9+18 by 9 do
for sx<span style=x"color: to#008080;">end</span> x+2<span dostyle="color: #008080;">for</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
ch = board[sy+sx+1]-'0'
<span style="color: #008080;">if</span> <span style="color: #000000;">sum9</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">45</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #004600;">false</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
sum9 += ch
<span style="color: #008080;">if</span> <span style="color: #000000;">nine</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">nines</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #004600;">false</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
nine[ch] = ch
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #008080;">return</span> <span style="color: #004600;">true</span>
if sum9!=45 then return 0 end if
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
if nine!=nines then return 0 end if
end for
<span style="color: #008080;">function</span> <span style="color: #000000;">solve</span><span style="color: #0000FF;">(</span><span style="color: #004080;">string</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">)</span>
end for
<span style="color: #0000FF;">{</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">solution</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">sequence</span> <span style="color: #000000;">valid</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">solved</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">plain_logic</span><span style="color: #0000FF;">(</span><span style="color: #000000;">board</span><span style="color: #0000FF;">)</span>
return 1
<span style="color: #008080;">if</span> <span style="color: #000000;">solved</span><span style="color: #0000FF;">=</span><span style="color: #000000;">INVALID</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #0000FF;">{{},</span><span style="color: #000000;">INVALID</span><span style="color: #0000FF;">}</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end function
<span style="color: #008080;">if</span> <span style="color: #000000;">solved</span><span style="color: #0000FF;">=</span><span style="color: #000000;">SOLVED</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #0000FF;">{{</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">},</span><span style="color: #000000;">SOLVED</span><span style="color: #0000FF;">}</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
 
<span style="color: #008080;">if</span> <span style="color: #000000;">solved</span><span style="color: #0000FF;">=</span><span style="color: #000000;">BRUTE</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #0000FF;">{{</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">},</span><span style="color: #000000;">BRUTE</span><span style="color: #0000FF;">}</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
function solve(string board, sequence valid={})
<span style="color: #008080;">if</span> <span style="color: #000000;">solved</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">INCOMPLETE</span> <span style="color: #008080;">then</span> <span style="color: #0000FF;">?</span><span style="color: #000000;">9</span><span style="color: #0000FF;">/</span><span style="color: #000000;">0</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
sequence solution, solutions
<span style="color: #000080;font-style:italic;">-- find the cell with the fewest options:
integer solved
-- (a possible improvement here would be to select the shortest
integer minopt, mindx
-- with the "most pairs" set, see swordfish etc above.)</span>
object vi
<span style="color: #004080;">integer</span> <span style="color: #000000;">minopt</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">10</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">mindx</span>
{solution,valid,solved} = plain_logic(board)
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span><span style="color: #0000FF;">*</span><span style="color: #000000;">9</span> <span style="color: #008080;">do</span>
if solved=INVALID then return {{},INVALID} end if
<span style="color: #004080;">object</span> <span style="color: #000000;">vi</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span>
if solved=SOLVED then return {{solution},SOLVED} end if
<span style="color: #008080;">if</span> <span style="color: #004080;">string</span><span style="color: #0000FF;">(</span><span style="color: #000000;">vi</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
if solved=BRUTE then return {{solution},BRUTE} end if
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">vi</span><span style="color: #0000FF;">)<=</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span> <span style="color: #0000FF;">?</span><span style="color: #000000;">9</span><span style="color: #0000FF;">/</span><span style="color: #000000;">0</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #000080;font-style:italic;">-- should be caught above</span>
if solved!=INCOMPLETE then ?9/0 end if
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">vi</span><span style="color: #0000FF;">)<</span><span style="color: #000000;">minopt</span> <span style="color: #008080;">then</span>
-- find the cell with the fewest options:
<span style="color: #000000;">minopt</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">vi</span><span style="color: #0000FF;">)</span>
-- (a possible improvement here would be to select the shortest
<span style="color: #000000;">mindx</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">i</span>
-- with the "most pairs" set, see swordfish etc above.)
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
minopt = 10
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
for i=1 to 9*9 do
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
vi = valid[i]
<span style="color: #004080;">sequence</span> <span style="color: #000000;">solutions</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
if string(vi) then
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">minopt</span> <span style="color: #008080;">do</span>
if length(vi)<=1 then ?9/0 end if -- should be caught above
<span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">mindx</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">valid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">mindx</span><span style="color: #0000FF;">][</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span>
if length(vi)<minopt then
<span style="color: #0000FF;">{</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">,</span><span style="color: #000000;">solved</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">solve</span><span style="color: #0000FF;">(</span><span style="color: #000000;">board</span><span style="color: #0000FF;">)</span>
minopt = length(vi)
<span style="color: #008080;">if</span> <span style="color: #000000;">solved</span><span style="color: #0000FF;">=</span><span style="color: #000000;">MULTIPLE</span> <span style="color: #008080;">then</span>
mindx = i
<span style="color: #008080;">return</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">,</span><span style="color: #000000;">MULTIPLE</span><span style="color: #0000FF;">}</span>
end if
<span style="color: #008080;">elsif</span> <span style="color: #000000;">solved</span><span style="color: #0000FF;">=</span><span style="color: #000000;">SOLVED</span>
end if
<span style="color: #008080;">or</span> <span style="color: #000000;">solved</span><span style="color: #0000FF;">=</span><span style="color: #000000;">BRUTE</span> <span style="color: #008080;">then</span>
end for
<span style="color: #008080;">if</span> <span style="color: #008080;">not</span> <span style="color: #7060A8;">find</span><span style="color: #0000FF;">(</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">],</span><span style="color: #000000;">solutions</span><span style="color: #0000FF;">)</span>
solutions = {}
<span style="color: #008080;">and</span> <span style="color: #000000;">validate</span><span style="color: #0000FF;">(</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">])</span> <span style="color: #008080;">then</span>
for i=1 to minopt do
<span style="color: #000000;">solutions</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">solutions</span><span style="color: #0000FF;">,</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">])</span>
board[mindx] = valid[mindx][i]
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
{solution,solved} = solve(board,valid)
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">solutions</span><span style="color: #0000FF;">)></span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span>
if solved=MULTIPLE then
<span style="color: #008080;">return</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">solutions</span><span style="color: #0000FF;">,</span><span style="color: #000000;">MULTIPLE</span><span style="color: #0000FF;">}</span>
return {solution,MULTIPLE}
<span style="color: #008080;">elsif</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">solutions</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
elsif solved=SOLVED
<span style="color: #008080;">return</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">solutions</span><span style="color: #0000FF;">,</span><span style="color: #000000;">BRUTE</span><span style="color: #0000FF;">}</span>
or solved=BRUTE then
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
if not find(solution[1],solutions)
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
and validate(solution[1]) then
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
solutions = append(solutions,solution[1])
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">solutions</span><span style="color: #0000FF;">)=</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span>
end if
<span style="color: #008080;">return</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">solutions</span><span style="color: #0000FF;">,</span><span style="color: #000000;">BRUTE</span><span style="color: #0000FF;">}</span>
if length(solutions)>1 then
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
return {solutions,MULTIPLE}
<span style="color: #008080;">return</span> <span style="color: #0000FF;">{{},</span><span style="color: #000000;">INVALID</span><span style="color: #0000FF;">}</span>
elsif length(solutions) then
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
return {solutions,BRUTE}
end if
<span style="color: #008080;">function</span> <span style="color: #000000;">test_one</span><span style="color: #0000FF;">(</span><span style="color: #004080;">string</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">)</span>
end if
<span style="color: #0000FF;">{</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">solutions</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">solved</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">solve</span><span style="color: #0000FF;">(</span><span style="color: #000000;">board</span><span style="color: #0000FF;">)</span>
end for
<span style="color: #004080;">string</span> <span style="color: #000000;">solution</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">desc</span>
if length(solutions)=1 then
<span style="color: #008080;">if</span> <span style="color: #000000;">solved</span><span style="color: #0000FF;">=</span><span style="color: #000000;">SOLVED</span> <span style="color: #008080;">then</span>
return {solutions,BRUTE}
<span style="color: #000000;">desc</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">"(logic)"</span>
end if
<span style="color: #008080;">elsif</span> <span style="color: #000000;">solved</span><span style="color: #0000FF;">=</span><span style="color: #000000;">BRUTE</span> <span style="color: #008080;">then</span>
return {{},INVALID}
<span style="color: #000000;">desc</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">"(brute force)"</span>
end function
<span style="color: #008080;">else</span>
 
<span style="color: #000000;">desc</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">"???"</span> <span style="color: #000080;font-style:italic;">-- INVALID/INCOMPLETE/MULTIPLE</span>
function test_one(string board)
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
sequence solutions
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">solutions</span><span style="color: #0000FF;">)=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
string solution, desc
<span style="color: #000000;">solution</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">board</span>
integer solved
<span style="color: #000000;">desc</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">"*** NO SOLUTIONS ***"</span>
{solutions,solved} = solve(board)
<span style="color: #008080;">elsif</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">solutions</span><span style="color: #0000FF;">)=</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span>
if solved=SOLVED then
<span style="color: #000000;">solution</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">solutions</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span>
desc = "(logic)"
<span style="color: #008080;">if</span> <span style="color: #008080;">not</span> <span style="color: #000000;">validate</span><span style="color: #0000FF;">(</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
elsif solved=BRUTE then
<span style="color: #000000;">desc</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">"*** ERROR ***"</span> <span style="color: #000080;font-style:italic;">-- (should never happen)</span>
desc = "(brute force)"
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
else
<span style="color: #008080;">else</span>
desc = "???" -- INVALID/INCOMPLETE/MULTIPLE
<span style="color: #000000;">solution</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">board</span>
end if
<span style="color: #000000;">desc</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">"*** MULTIPLE SOLUTIONS ***"</span>
if length(solutions)=0 then
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
solution = board
<span style="color: #008080;">return</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">,</span><span style="color: #000000;">desc</span><span style="color: #0000FF;">}</span>
desc = "*** NO SOLUTIONS ***"
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
elsif length(solutions)=1 then
solution = solutions[1]
<span style="color: #000080;font-style:italic;">--NB Blank cells can be represented by any character &lt;'1'. Spaces are not recommended since
if not validate(solution) then
-- they can all too easily be converted to tabs by copy/paste/save. In particular, ? and
desc = "*** ERROR ***" -- (should never happen)
-- _ are NOT valid characters for representing a blank square. Use any of .0-* instead.</span>
end if
else
<span style="color: #008080;">constant</span> <span style="color: #000000;">tests</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span>
solution = board
<span style="color: #008000;">"..............3.85..1.2.......5.7.....4...1...9.......5......73..2.1........4...9"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.01s, (logic))
desc = "*** MULTIPLE SOLUTIONS ***"
-- row/col elimination (was 8s w/o logic first)</span>
end if
<span style="color: #008000;">"000000036840000000000000020000203000010000700000600400000410050003000200600000000"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.04s, (brute force))</span>
return {solution,desc}
<span style="color: #008000;">".......39.....1..5..3.5.8....8.9...6.7...2...1..4.......9.8..5..2....6..4..7....."</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (1.12s, (brute force))</span>
end function
<span style="color: #008000;">"000037600000600090008000004090000001600000009300000040700000800010009000002540000"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s, (logic))</span>
 
<span style="color: #008000;">"....839..1......3...4....7..42.3....6.......4....7..1..2........8...92.....25...6"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.04s, (brute force))</span>
--NB Blank cells can be represented by any character <'1'. Spaces are not recommended since
<span style="color: #008000;">"..1..5.7.92.6.......8...6...9..2.4.1.........3.4.8..9...7...3.......7.69.1.8..7.."</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s, (logic))
-- they can all too easily be converted to tabs by copy/paste/save. In particular, ? and
-- (the following takes ~8s when checking for multiple solutions)</span>
-- _ are NOT valid characters for representing a blank square. Use any of .0-* instead.
<span style="color: #008000;">"--3------4---8--36--8---1---4--6--73---9----------2--5--4-7--686--------7--6--5--"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.01s, (brute force))</span>
 
<span style="color: #008000;">"..3.2.6..9..3.5..1..18.64....81.29..7.......8..67.82....26.95..8..2.3..9..5.1.3.."</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s, (logic))</span>
constant tests = {
<span style="color: #008000;">"--4-5--6--6-1--8-93----7----8----5-----4-3-----6----7----2----61-5--4-3--2--7-1--"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s, (logic))
"..............3.85..1.2.......5.7.....4...1...9.......5......73..2.1........4...9", -- (0.01s, (logic))
-- x-wings</span>
-- row/col elimination (was 8s w/o logic first)
<span style="color: #008000;">".4398.25.6..425...2....1.949....4.7.3..6.8...41.2.9..382.5.........4...553489.71."</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s, (logic))</span>
"000000036840000000000000020000203000010000700000600400000410050003000200600000000", -- (0.04s, (brute force))
<span style="color: #008000;">".9...4..7.39....79.1.8.5..3.5.8...4.858.9...6.73...2...1.2.4....97.6..9.8..5..2.4..35.6..4..72..6...8."</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (10.12s00s, (brute forcelogic))
-- "AL Escargot", so-called "hardest sudoku"</span>
"000037600000600090008000004090000001600000009300000040700000800010009000002540000", -- (0.00s, (logic))
<span style="color: #008000;">"1....8397.9.1.3..2...38..96.4.5...7.53.42.39...1.6.8...26....4...3.7..1..2.1..4.....8.7..927...3..25...6"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.04s26s, (brute force))</span>
<span style="color: #008000;">"12.3.1..5.7435.92.6..1....4.8...6...9.54..2.4.16...7.......3.4.8..9...731..5.3......9.7.69.1.8..76...8"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s48s, (logicbrute force))</span>
<span style="color: #008000;">"12.4..3..3...1..5...6...1..7...9.....4.6.3.....3..2...5...8.7....7.....5.......98"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (1.07s, (brute force))</span>
-- (the following takes ~8s when checking for multiple solutions)
<span style="color: #008000;">"394..267....3..4..5..69..2..45...9..6.......7..7...58..1..67..8..9..8....264..735"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s, (logic))</span>
"--3------4---8--36--8---1---4--6--73---9----------2--5--4-7--686--------7--6--5--", -- (0.01s, (brute force))
<span style="color: #008000;">"4....3.2.6.5...8.9..3.5...1..18.64.2.7..81.29.1.7.9.....4.8..67.82.3.5..26.95.2.8..2.37..9.6.5...8.1.3.....6"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s01s, (logicbrute force))</span>
<span style="color: #008000;">"5...7....6..195....98....6.8...6...34..8.3..17...2...6.6....28....419..5....8..79"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s, (logic))</span>
"--4-5--6--6-1--8-93----7----8----5-----4-3-----6----7----2----61-5--4-3--2--7-1--", -- (0.00s, (logic))
<span style="color: #008000;">"503600009010002600900000080000700005006804100200003000030000008004300050800006702"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s, (logic))</span>
-- x-wings
<span style="color: #008000;">"53.4398.25.6247..425...2...8..1.949.7.39.2.4.78.372.49.62.898..7.4179.2.9..382.58.....3.5.696..41.3..553489.715.69..1."</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s, (logic))</span>
<span style="color: #008000;">"530070000600195000098000060800060003400803001700020006060000280000419005000080079"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s, (logic))
".9...4..7.....79..8........4.58.....3.......2.....97.6........4..35.....2..6...8.", -- (0.00s, (logic))
-- set exclusion</span>
-- "AL Escargot", so-called "hardest sudoku"
<span style="1color: #008000;">"75..9..746961.9..33524..2...879.2.96.6.51..7.8.53..9..2.1..8328.65..26....4...3.9...2..1..4......7..7.484..3..79"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.26s00s, (brute forcelogic))
-- Worlds hardest sudoku:</span>
"12.3....435....1....4........54..2..6...7.........8.9...31..5.......9.7.....6...8", -- (0.48s, (brute force))
<span style="color: #008000;">"800000000003600000070090200050007000000045700000100030001000068008500010090000400"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.21s, (brute force))</span>
"12.4..3..3...1..5...6...1..7...9.....4.6.3.....3..2...5...8.7....7.....5.......98", -- (1.07s, (brute force))
<span style="color: #008000;">"819--5-----2---75--371-4-6-4--59-1--7--3-8--2--3-62--7-5-7-921--64---9-----2--438"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s, (logic))</span>
"394..267....3..4..5..69..2..45...9..6.......7..7...58..1..67..8..9..8....264..735", -- (0.00s, (logic))
<span style="4color: #008000;">"85...24..72.6.5...8.9..34....1....2.1.7..23.5..1.9.....4.8....3.5....2..8..7..617.5...8.1.....36.64."</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.01s, (brute forcelogic))</span>
<span style="5color: #008000;">"9..2..5.7..4..6..1953...3.98....6.8..9.6.2..34....5..8.3..177..4.2.37..6.6..1..28.5..2.419.4.5..1..86..799"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s17s, (logicbrute force))</span>
<span style="color: #008000;">"97.3...6..6.75.........8.5.......67.....3.....539..2..7...25.....2.1...8.4...73.."</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.00s, (logic))
"503600009010002600900000080000700005006804100200003000030000008004300050800006702", -- (0.00s, (logic))
-- "the beast" (an earlier algorithm took 318s (5min 18s) on this):</span>
"53..247....2...8..1..7.39.2..8.72.49.2.98..7.79.....8.....3.5.696..1.3...5.69..1.", -- (0.00s, (logic))
<span style="color: #008000;">"000060080020000000001000000070000102500030000000000400004201000300700600000000050"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (0.03s, (brute force))</span>
"530070000600195000098000060800060003400803001700020006060000280000419005000080079", -- (0.00s, (logic))
<span style="color: #0000FF;">$},</span>
-- set exclusion
"75..9..46961...3524.....79.2..6.1..7.8.....2.1..328.65.........3.9...2.484..3..79", -- (0.00s, (logic))
<span style="color: #000000;">lt</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">tests</span><span style="color: #0000FF;">),</span>
-- Worlds hardest sudoku:
<span style="color: #000000;">run_one_test</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
"800000000003600000070090200050007000000045700000100030001000068008500010090000400", -- (0.21s, (brute force))
"819--5-----2---75--371-4-6-4--59-1--7--3-8--2--3-62--7-5-7-921--64---9-----2--438", -- (0.00s, (logic))
<span style="color: #008080;">constant</span> <span style="color: #000000;">l</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">" x x x | x x x | x x x "</span><span style="color: #0000FF;">,</span>
"85...24..72......9..4.........1.7..23.5...9...4...........8..7..17..........36.4.", -- (0.01s, (logic))
<span style="color: #000000;">s</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">"-------+-------+-------"</span><span style="color: #0000FF;">,</span>
"9..2..5...4..6..3...3.....6...9..2......5..8...7..4..37.....1...5..2..4...1..6..9", -- (0.17s, (brute force))
<span style="color: #000000;">l3</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">join</span><span style="color: #0000FF;">({</span><span style="color: #000000;">l</span><span style="color: #0000FF;">,</span><span style="color: #000000;">l</span><span style="color: #0000FF;">,</span><span style="color: #000000;">l</span><span style="color: #0000FF;">},</span><span style="color: #008000;">"\n"</span><span style="color: #0000FF;">),</span>
"97.3...6..6.75.........8.5.......67.....3.....539..2..7...25.....2.1...8.4...73..", -- (0.00s, (logic))
<span style="color: #000000;">fmt</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">substitute</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">join</span><span style="color: #0000FF;">({</span><span style="color: #000000;">l3</span><span style="color: #0000FF;">,</span><span style="color: #000000;">s</span><span style="color: #0000FF;">,</span><span style="color: #000000;">l3</span><span style="color: #0000FF;">,</span><span style="color: #000000;">s</span><span style="color: #0000FF;">,</span><span style="color: #000000;">l3</span><span style="color: #0000FF;">},</span><span style="color: #008000;">"\n"</span><span style="color: #0000FF;">),</span><span style="color: #008000;">"x"</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"%c"</span><span style="color: #0000FF;">)&</span><span style="color: #008000;">"\n"</span>
-- "the beast" (an earlier algorithm took 318s (5min 18s) on this):
"000060080020000000001000000070000102500030000000000400004201000300700600000000050", -- (0.03s, (brute force))
<span style="color: #008080;">procedure</span> <span style="color: #000000;">test</span><span style="color: #0000FF;">()</span>
$},
<span style="color: #004080;">string</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (81 characters)</span>
 
<span style="color: #000000;">solution</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">desc</span>
lt = length(tests),
<span style="color: #004080;">atom</span> <span style="color: #000000;">t0</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">time</span><span style="color: #0000FF;">()</span>
run_one_test = 0
<span style="color: #008080;">if</span> <span style="color: #000000;">run_one_test</span> <span style="color: #008080;">then</span>
 
<span style="color: #000000;">board</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">tests</span><span style="color: #0000FF;">[</span><span style="color: #000000;">run_one_test</span><span style="color: #0000FF;">]</span>
constant l = " x x x | x x x | x x x ",
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">fmt</span><span style="color: #0000FF;">,</span><span style="color: #000000;">board</span><span style="color: #0000FF;">)</span>
s = "-------+-------+-------",
<span style="color: #0000FF;">{</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">,</span><span style="color: #000000;">desc</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">test_one</span><span style="color: #0000FF;">(</span><span style="color: #000000;">board</span><span style="color: #0000FF;">)</span>
l3 = join({l,l,l},"\n"),
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">)!=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
fmt = substitute(join({l3,s,l3,s,l3},"\n"),"x","%c")&"\n"
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"solution:\n"</span><span style="color: #0000FF;">)</span>
 
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">fmt</span><span style="color: #0000FF;">,</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">)</span>
procedure print_board(string board)
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
printf(1,fmt,board)
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"%s, %3.2fs\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">desc</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">time</span><span style="color: #0000FF;">()-</span><span style="color: #000000;">t0</span><span style="color: #0000FF;">})</span>
end procedure
<span style="color: #008080;">else</span>
 
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">lt</span> <span style="color: #008080;">do</span>
procedure test()
<span style="color: #004080;">atom</span> <span style="color: #000000;">t1</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">time</span><span style="color: #0000FF;">()</span>
string board -- (81 characters)
<span style="color: #000000;">board</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">tests</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span>
string solution, desc
<span style="color: #0000FF;">{</span><span style="color: #000000;">solution</span><span style="color: #0000FF;">,</span><span style="color: #000000;">desc</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">test_one</span><span style="color: #0000FF;">(</span><span style="color: #000000;">board</span><span style="color: #0000FF;">)</span>
atom t0 = time()
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">" \"%s\", -- (%3.2fs, %s)\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">board</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">time</span><span style="color: #0000FF;">()-</span><span style="color: #000000;">t1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">desc</span><span style="color: #0000FF;">})</span>
if run_one_test then
<span style="color: #000080;font-style:italic;">-- printf(1," \"%s\", -- (%3.2fs, %s)\n",{solution,time()-t1,desc})</span>
board = tests[run_one_test]
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
print_board(board)
<span style="color: #000000;">t0</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">time</span><span style="color: #0000FF;">()-</span><span style="color: #000000;">t0</span>
{solution,desc} = test_one(board)
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"%d puzzles solved in %3.2fs (av %3.2fs)\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">lt</span><span style="color: #0000FF;">,</span><span style="color: #000000;">t0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">t0</span><span style="color: #0000FF;">/</span><span style="color: #000000;">lt</span><span style="color: #0000FF;">})</span>
if length(solution)!=0 then
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
printf(1,"solution:\n")
<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span>
print_board(solution)
<span style="color: #000000;">test</span><span style="color: #0000FF;">()</span>
end if
<!--</lang>-->
printf(1,"%s, %3.2fs\n",{desc,time()-t0})
else
for i=1 to lt do
atom t1 = time()
board = tests[i]
{solution,desc} = test_one(board)
printf(1," \"%s\", -- (%3.2fs, %s)\n",{board,time()-t1,desc})
-- printf(1," \"%s\", -- (%3.2fs, %s)\n",{solution,time()-t1,desc})
end for
t0 = time()-t0
printf(1,"%d puzzles solved in %3.2fs (av %3.2fs)\n",{lt,t0,t0/lt})
end if
end procedure
test()</lang>
{{out}}
<pre>
Petelomax
7,794

edits

Retrieved from "https://rosettacode.org/wiki/Special:MobileDiff/121416"